Abstract: A cargo hold having a plurality of spaces, which are formed by a longitudinal bulkhead and a transverse bulkhead intersecting each other and store crude oil, comprises a void space located at least one corner among corners formed by intersection of the longitudinal bulkhead and the transverse bulkhead, wherein the void space is formed of a void space structure having one side end and the other side end sealed by and fixed to the longitudinal bulkhead and the transverse bulkhead, respectively, thereby forming an empty space inside the bulkheads. The vessel cargo hold prevents a danger, such as fire and explosion, which may occur during the maintenance or repair of the vessel cargo hold for storing crude oil, and decreases work or the like required for the maintenance or repair of the cargo hold.

Abstract: Disclosed herein is a self-propelled personal water craft including a parabolic hull. The hull has a bow, mid-section and stern. The mid-section has substantially reduced diameter compared with the bow and stern section defining an hour-glass hull shape. The hull including an upper portion and a lower portion, a hollow space is created between the upper and lower portions and defines a central portion. The lower portion includes structure for manipulating water drag. Additionally, the craft includes a motor member for propelling the craft. In an exemplary embodiment, the motor member includes an axial flow jet pump.

Abstract: A ship according to the invention for conveying and setting up offshore structures having: a hull with a U-shaped cross-section having an open stern and projections of the side walls extending at the rear beyond the rear edge of the floor, jack-up leg systems with jack-up legs integrated in the hull that are movable in a vertical direction with their bottom ends in positions below the floor, and a crane that can move on the top edges of the side walls.

Abstract: A kayak comprises a hull with a relatively narrow cross sectional underwater width for increasing speed and efficiency of the kayak moving through water and first and second pairs of convex surfaces for providing kayak stability.

Abstract: A modularized unmanned marine surface vehicle contains control section and propulsion section. The control section is composed of bow section, control cabin, probing module, communication module and conjunction module. The propulsion section contains an energy cabin and a power plant cabin. The conjunction module can be combined with the energy cabin as a complete unmanned marine surface vehicle. The probing module contains probing instruments and equipment. The propulsion section can be battery-powered, gasoline-powered or diesel-powered. The propulsion section can be equipped with a propeller, a water jet or a turbine jet propeller of high power or low power as the power source assembly.